To verify the accuracy and the clinical application of the coronary artery calcium score measurement on coronary CT angiography (CCTA).
The study enrolled 1093 patients (56.86 ± 9.47 years old, 454 males) who underwent both coronary artery calcium score plain CT and CCTA scans from 2018 to 2019. Calcium volume (CCTA-CV) and Agatston score (CCTA-AS) were both measured from the CCTA images taking the mean aortic attenuation value pluses twice the standard deviation as the calcium detection threshold. Calcium volume (Plain CT-CV) and Agatston score (Plain CT-AS) were also measured on plain CT as the gold standard.
Pearson correlation analysis showed good correlations between the CCTA-CV and Plain CT- CV in main branches and total volume (r2 = 0.96, 0.96, 0.92, 0.93, 0.96 for LM, LAD, LCX, RCA, and total volume, respectively, ps < 0.001). CCTA-AS also correlated linearly with Plain CT-AS with a good correlation coefficient (r2 = 0.96, 0.97, 0.93, 0.94, 0.97 for LM, LAD, LCX, RCA, and total Agatston score, respectively, ps < 0.001).Radiation dose were 1.42 ± 0.13 mSv, and 1.87 ± 0.12 mSv for CCTA scan only and for Plain CT + CCTA (t = -− 11.82, p < 0.001). CCTA missed 35 cases’ calcification with the mean calcium volume = 4.59 mm3 and mean Agatston score = 2.31, while CCTA also rediscovered 13 cases’ calcification with the mean calcium volume = 3.92 mm3 and mean Agatston score = 5.21. Agatston grades Kappa between the two methods was 0.864 (p < 0.001). Additionally, age, male, diabetes mellitus, typical symptoms, smoke, and cerebrovascular disease were the impact factors for both Plain CT-AS and CCTA-AS (ps < 0.001).
Calcium volume and Agatston score can be accurately measured from CCTA images only with ~ 25% radiation dose reduction. Even though there were several missing or newly found calcification cases, CCTA-AS could indicate the risk stratification in the clinics.